VideoDecodeAccelerator now SupportsWeakPtr instead of being RefCountedThreadSafe.

media/filters/gpu_video_decoder.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_FILTERS_GPU_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_GPU_VIDEO_DECODER_H_
 
 #include <deque>
 #include <list>
 #include <map>
@@ skipping 101 matching lines @@
       const scoped_refptr<VideoFrame>& frame);
 
   // Indicate the picturebuffer can be reused by the decoder.
   void ReusePictureBuffer(int64 picture_buffer_id);
 
   void RecordBufferTimeData(
       const BitstreamBuffer& bitstream_buffer, const Buffer& buffer);
   void GetBufferTimeData(
       int32 id, base::TimeDelta* timestamp, base::TimeDelta* duration);
 
+  // Set |vda_| and |weak_vda_| on the VDA thread (in practice the render
+  // thread).
+  void SetVDA(VideoDecodeAccelerator* vda);
+
   // A shared memory segment and its allocated size.
   struct SHMBuffer {
     SHMBuffer(base::SharedMemory* m, size_t s);
     ~SHMBuffer();
     base::SharedMemory* shm;
     size_t size;
   };
 
   // Request a shared-memory segment of at least |min_size| bytes.  Will
   // allocate as necessary.  Caller does not own returned pointer.
@@ skipping 19 matching lines @@
   // if they arrive on other loops.
   scoped_refptr<base::MessageLoopProxy> gvd_loop_proxy_;
 
   // Message loop on which to makes all calls to vda_.  (beware this loop may be
   // paused during the Pause/Flush/Stop dance PipelineImpl::Stop() goes
   // through).
   scoped_refptr<base::MessageLoopProxy> vda_loop_proxy_;
 
   scoped_refptr<Factories> factories_;
 
-  // Populated during Initialize() (on success) and unchanged thereafter.
-  scoped_refptr<VideoDecodeAccelerator> vda_;
+  // Populated during Initialize() via SetVDA() (on success) and unchanged
+  // until an error occurs
+  scoped_ptr<VideoDecodeAccelerator> vda_;
+  // Used to post tasks from the GVD thread to the VDA thread safely.
+  base::WeakPtr<VideoDecodeAccelerator> weak_vda_;
 
   // Callbacks that are !is_null() only during their respective operation being
   // asynchronously executed.
   ReadCB pending_read_cb_;
   base::Closure pending_reset_cb_;
 
   State state_;
 
   // Is a demuxer read in flight?
   bool demuxer_read_in_progress_;
@@ skipping 37 matching lines @@
 
   // Indicates decoding error occurred.
   bool error_occured_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_GPU_VIDEO_DECODER_H_